Pipe testing machine



sept. 13, 1932. w, T, MAHL 1,876,711

' PIPE TESTING MAGHINE 1 Fned June 19, 1930 2 sheets-sheet 1 Sept. 13, 1932. w. T. MAI-" A v PIPE TESTING MACHINE.

Filed lJune 19. 195@ 2 Sheets-Sheet 2 y lwenfar: WQLTEE 7., MHHLH, Y g4 M .NQMLN I Patented Sept. 13, 1932 UNITED STATES rATE-NT oFFlcE WALTER T. MA'HLA, or roaArN, oHro, AssrGNoE To NATIONAL TUBE COMPANY, 1A

' eoRroRATIoN or NEW JERSEY PIPE TESTING MACHINE .'Application led June 19, 1930. Serial No. 462,278.

This invention relates to testing machines for conduit pipe of that type wherein hydrostatic or like fluid pressure is built up in the pipe to ascertain if there are any leaking welds or joints, and the primary object in -view is to provide a pipe testing machine which will operate automatically and more rapidly than known machines of Vthis class, to thereby reduce costs of labor and at,the same time materially increase production.

'Numerous other objects and advantages will become apparent in view of the following description and claims taken in conjunction with the drawings, wherein:

Figure 1 is a top plan of the improved machine, broken through and moved together to conserve space in the drawings.

Figure 2 is an end elevation.

Figure 3 is al sectionalview taken on the line III-III of Figure 1.

Figure 4 is an enlarged transverse vertical sectional view of 'an automatically operating valve assembly for controlling admission of with a worm 9, see

fluid pressure into the pipe to be tested.

Figure 5 is a sectional view taken on the line V-V of Figure 4.

The numeral 5 generally designates the supporting pedestals or castings of thev machine and 5a the longitudinal bed-plate or frame which is formed with side rails 5b.

The complete cycle of operations of the machine is controlled by a cam 6, here shown as of the drum or barrel type and formed with a track or groove 6a, said cam being rotatably mounted at the one extremity of the machine on a shaft 7, which is suitably journaled in bearing brackets 7 a. The shaft 7 has secured thereon a worm gear 8 in mesh Figure 2, which is secured on a jack-shaft 10, the latter in turn having secured thereon a' pulley 10a, the drive being applied to said pulley from a motor M.

The bed-plate or frame 5a is provided with a; bearing housing 12 and bearings 12a, in which is mounted for longitudinal sliding movement a plunger 13, said plunger being reciprocated by the cam 6 through the medium of cam levers 14 and 15, which are suitably secured on a .pin or stub shaft 16' having bearing in a bracket 16a, the one extremity of vin Fig. 4, has

lever 14 being formed with a yoke or fork 14erl which engages the one extremity of plunger 13.

A feature of the present invention is the provision of an autmatically operating valve assembly, shown in detail in Fig. 4, which controls the admission of luid or Vhydrostatic pipe to be tested and which pressure into the plunger 13 and assembly is mounted in the will now be described.

A cross-head 17 is secured in stable position with respect to the housing 12 and spaced a suitable distance therefrom by bars 18, and secured to said cross-head is a pin 19 headed at one end as at 19a, and provided with a longitudinal bore 19?) which terminates at one extremity in a right-angular outlet v19a and at its opposite extremity in a nipple portion to which the water orlike fluid pressure line 20 is attached. The interior of the plungerv 13 is cored out or formed with a longitudinal bore 21 which is shouldered and houses the valve assemblies at its opposite extremities. The assembly on the right, as viewed in Fig. 4, comprises a sleeve 22, cage 23 formed with ports 23a opening into a chamber 23?), and a cap 24, the latter being secured to the end of the plunger 13 to retain the parts in assembled position, and the pin 19 is then inserted through the foregoing assembly J'and secured to the cross-head 17 in relatively stationary position.

The opposite extremity of the plunger 13, or the extremity thereof on the left as viewed detachably secured thereto a flanged cap or housing 25 which when removed permits valve assembly to be applied in position in said plunger. These parts as shown comprise a cage or sleeve 26 formed with ,ports 26a and 266, a valve stem or pin 27 formed with reduced portion or neck 27a, and an annular sleeve 28 or analogous member provided with a port 28a. In assembling, the cage or sleeve 26 and sleeve 28 may be applied on the stem 27 and the parts inserted in the one extremity of the plunger 13, as will be readily understood from the provided around the central portion of cage 26.

drawings, a chamber 29 being the remaining parts of the ports 28a and at its opposite extremity with the port 26a when the plunger is inthe position shown.

The cap or housing 25 has adjustably threaded thereon a collar 32, against which a spring 33 abuts, and next to the spring is a slidable stop head 34, which is interiorly flanged and held in assembled relation by a' collar 35 which is threaded on the end of ca' 25.

he interior of the cap 25 is cored out to receive 'an assembly comprising a pin 36, washer 36a, bushing or sleeve 37 and plunger head 38, the latter being formed with a stem 38a, which is formed with a longitudinal bore 386 communicating with ports 380 formed in said pin 36 and through said ports with a chamber 39 which is provided around the pin at this point.

The plunger head 38 receives the one end of the pipe to be tested and is therefore provided 'with an interior bushing or gland to prevent leakage of high pressure water or fluid at this point. It will also be understood that suitable glands may be provided adjacent the valve cages 23 and 26 and at other points where it may be necessary to prevent leakage. Y

The opposite end of the pipe to be tested is inserted in a backstop 40, which may be of the conventional design, having a small bore 40a through its center, to permit escape of air and Huid, said bore heilig of a diameter small enough to cause a. back pressure sulficient to test the pipe.

To prevent buckling of the pipe undergoing test, hold-down arms 41, note Fig. 3, are provided, said arms being secured on a shaft 42, which is mounted in bearing brackets 43 secured to the bed-plate 5a. These arms 41 are also operated from the cam 6, a cranklever 44 being secured on the one extremity of shaft 42 and provided with a cam roller 44a engaging in the groove 6a of said cam.

The operation of the machine, briefly stated, when used for testing conduit pipe, is as follows The pipe, as it comes from the threading machines, is usually disposed in a single layer on a platform or table, a fragment of whieh'is shown at 45, Fig. 1, for the purposes of illustration, and inspected for scrap, after which the pipe may be fed into the machine manually, each pipe being placed lengthwise between the backstop 40 and plunger head 38.

High pressure fluid or water is admitted into passage or bore 196 of pin 19, which is held stationary at all times. As cam 6 revolves, it reciprocates plunger 13 through the medium of levers 14 and 15. As plunger 13 moves forward, it successively uncovers outlet 190 and permits the water to pass into chamber 236 through passage 30 and into chamber 29, and also advances plunger head 38, valve stem 27 and valve cage 26, until head 38 engages the pipe to be tested. When the head 38 engages the pipe, the head 38 and stem 27 are held stationarywhile the plunger 13 and cage 26 continue to advance, uncovering port 26a and permitting water under pressure to pass through passage31 into chamber 39 and thence through port 380 and bore 386 into the pipe undergoing test. The cam 6 is timed so that the plunger is held in its forward position a sufficient length of time for the proper pressure to build up in the pipe, after which the plunger 13 moves back and permits removal of the pipe and replacement thereof by the succeeding pipe to be tested. As the plunger moves back, the spring 33 causes the valve stem 27 to move to closed position and thereby shut ofi' the water until the next forward stroke of the plunger.

It will be noted that if there is no pipe in position for test, the plunger head 38 and valve stem 27 remain stationary with respect to the plunger 13, so that the valve remains closed and prevents flow of fluid or water under pressure.

The many advantages afforded by the improved automatic testing machine over the hand valve method of testing pipe will be readily apparent. The machine operates steadily and in timed relation so that its output 4can be accurately determined in View of the stock on hand and a definite and regular speed may be set in view of other operations and the shop output in general. All that is required is a man to feed the pipe to the machine, the remaining part of the operation being automatic, in contradistinction to the hand valve method where two men were required to make the test.

What is claimed as new is:

1. I'n a hydrostatic testing mechanism of the class specified, a plunger, means for reciprocating said plunger, a head member and valve slidably mounted for limited movement in said plunger, said plunger and said head being reeiprocated as a unit to engage the said head withthe pipe to betested, said head having a passage therethroughterminating in .a socket adapted to fit over and communicate with one end of 'the pipe to be tested, said head having a stop, a spring mounted on said plunger and engaged between said head and said stop on said plunger so as to normally hold said head and valve in extended position, said plunger having a plurality of passages, one of said passages most'position relative to said plunger by said spring.

2. In a hydrostatic testing mechanism of the class specified, a plunger, power operated A cam means for reciprocatingsaid plunger, a

head member and Valve unit slidably mounted in said plunger, said plunger and said head being reciprocated as a unit to engage said head with the pipe to be tested, said head and valve being adapted to be heldy stationary when engaged with said pipe while said plunger is adapted to continue its movement for a limited travel, said head having a passage therethrough terminating in a socket adapted to fit over'and communicate with one end of the pipe to be tested, resilient means for normally holding said head and valve in extended position, said plunger lhaving a plurality of passages, one of said passages extending to said valve and another of said passages extending from said valve to said passage in said head, means for supplying water under pressure to said one of said passages and said valve being adapted to establish communication between said pas- -sages in said plunger and said head to admit water under pressure to the pipe bein tested when said plunger is moved forward y relative to said valve and said head, and said valve being adapted to automatically move to closed position when said head and valve valve to said passage in saidhead, valve controlled means for supplying fluid under pressure to said one of said passages and said first named valve being adapted to establish communication between said passages in said plunger and said head to admit iuid under4 pressure to the pipe being tested when said plunger is moved forwardly relative to said d valve and said head and said valve being adapted to automatically move -to closed position when said head and valve are moved to their forwardmost position relative to said plunger by said resilient means.

In testimony whereof, I have hereunto set m hand.

y WALTER T. MAHLA.

are moved to their forwardmost position relau.

tive to said plunger by said resilient means.

3. In a hydrostatic testing mechanism of the class specified, a plunger, poweroperated cam for reciprocating said plunger, a head member and valve slidably mounted for limited movement in said plunger, said plunger and said head being reciprocated as a unit to engage said head with the pipe to be v tested, said head and valve being adapted to be held stationary when engaged with said pipe whilesaid plunger is adapted to con-l tinue its movement for a limited travel, said head having a passage therethrough terminating in a socket adapted to fit over and communicate with one end of the pipe to be tested, resilient means for normally holding said head and valve in extended position, said plunger' having a plurality of passages, one of said passages extending to said valve and another of said passages extending from said 

